ZyXEL Communications MAX-306M1 User Manual

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 Chapter 7 The LAN Configuration Screens
User’s Guide
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• None - the WiMAX Modem will not send any RIP packets and will ignore any RIP 
packets received.
The Version field controls the format and the broadcasting method of the RIP 
packets that the WiMAX Modem sends (it recognizes both formats when 
receiving). RIP-1 is universally supported; but RIP-2 carries more information. 
RIP-1 is probably adequate for most networks, unless you have an unusual 
network topology.
Both RIP-2B and RIP-2M sends the routing data in RIP-2 format; the difference 
being that RIP-2B uses subnet broadcasting while RIP-2M uses multicasting.
7.6.6  Multicast
Traditionally, IP packets are transmitted in one of either two ways - Unicast (1 
sender - 1 recipient) or Broadcast (1 sender - everybody on the network). 
Multicast delivers IP packets to a group of hosts on the network - not everybody 
and not just 1.
IGMP (Internet Group Multicast Protocol) is a network-layer protocol used to 
establish membership in a Multicast group - it is not used to carry user data. IGMP 
version 2 (RFC 2236) is an improvement over version 1 (RFC 1112) but IGMP 
version 1 is still in wide use. If you would like to read more detailed information 
about interoperability between IGMP version 2 and version 1, please see sections 
4 and 5 of RFC 2236. The class D IP address is used to identify host groups and 
can be in the range 224.0.0.0 to 239.255.255.255. The address 224.0.0.0 is not 
assigned to any group and is used by IP multicast computers. The address 
224.0.0.1 is used for query messages and is assigned to the permanent group of 
all IP hosts (including gateways). All hosts must join the 224.0.0.1 group in order 
to participate in IGMP. The address 224.0.0.2 is assigned to the multicast routers 
group.
The WiMAX Modem supports both IGMP version 1 (IGMP-v1) and IGMP version 2 
(IGMP-v2). At start up, the WiMAX Modem queries all directly connected 
networks to gather group membership. After that, the WiMAX Modem periodically 
updates this information. IP multicasting can be enabled/disabled on the WiMAX 
Modem LAN and/or WAN interfaces in the web configurator (LAN; WAN). Select 
None to disable IP multicasting on these interfaces.